Decomposition of semiconductors

Likewise, irradiation of an n-Si electrode in an aqueous electrolyte efficiently forms an insulating SiOx interface [3]. Reductive decomposition of semiconductors is rarely observed, although it has been claimed that certain p-type III-V semiconductors in the phosphide family decompose to form PH3. 

H. Gerischer and W. Mindt, The mechanisms of tiie decomposition of semiconductors by electrochemical oxidation and reduction, Electrochim. Acta 13, 1329, 1968. 

Fig. 2 Schematic drawings of the band diagram representing decomposition of semiconductor under anodization.

We have seen that the rate determining step in anodic decomposition of semiconductors consumes holes. 

It is our general experience that the cathodic decomposition of semiconductor is very much favoured by the creation of dislocations, for instance by mechcmical polishing. Only when a high cathodic voltage is applied, the decomposition reaction begins also at smooth faces of semiconductors like ZnO and CdS. 

Stability criteria for electrolytic decomposition of semiconductors (a) stable, (b) Instable,... 

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